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Fully integrated circuits printed directly onto fabric

______________________________   Fully integrated circuits printed directly onto fabric   Researchers have successfully incorporated washable, stretchable and breathable electronic circuits into fabric, opening up new possibilities for smart textiles and wearable electronics. The circuits were made with cheap, safe and environmentally friendly inks, and printed using conventional inkjet printing techniques. The researchers, from the University of Cambridge, working with colleagues in Italy and China, have demonstrated how graphene -- a two-dimensional form of carbon -- can be directly printed onto fabric to produce integrated electronic circuits which are comfortable to wear and can survive up to 20 cycles in a typical washing machine. The new textile electronic devices are based on low-cost, sustainable and scalable inkjet printing of inks based on graphene and other two-dimensional materials, and are produced by standard processing techniques. The...
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SEMICONDUCTOR n-type

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   when a small amount of pentavalent impurities is added to a pure semiconductor, it is known as an n-type semiconductor. The addition of pentavalent impurities produces a large number of free electrons in the semiconductor crystal, from the bonding diagram.  Since arsenic is a pentavalent element, the four valence electrons of germanium form a covalent bond with the arsenic atom and the electrons of the fifth valence are left free producing n-type conductors.  SEMICONDUCTOR p-type    When a small amount of trivalent impurities is added to a pure semiconductor, it is called p-type semiconductor. Such impurities that produce the p-type Semiconductor are known as acceptor impurities because the holes created can accept the electrons. The formation of the p-type semiconductor can be explained with the help of the connection diagram mentioned above.  When a small amount of trivalent impurities such as gallium is added to the pure germa...
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DIODE

    Unless their non-critical diodes are not generally used to provide a voltage drop, although they are frequently used for 'diode-O' 2 supplies together, or as mentioned elsewhere, they provide protection for reverse gear. For lower forward voltages, it is more common to use Schottky, which has a forward drop of 0.3 V or so. You usually do not use a high-value R to drop voltage unless you are working in very high voltage / low current applications. for rails below 5 V, a 0.7V drop is generally intolerable; although it can be insignificant in systems that use 12V or high. Again, your specific application. Zener can be used in both derivations and serial topologies, depending on what you try to do, but they are only used in low precision applications. It is quite common today in computer electronics to have secondary 1.2V supplies that can be maintained at a 5mV tolerance or change dynamically in steps of 5mV, such as the SVID rails on a CPU. Silicon Diode  ...
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